This invention relates generally to devices for disposing of used medical equipment or waste materials, and particularly to a method and apparatus for the containment, transportation, and safe disposal of biologically infectious or potentially hazardous waste materials.
The disposal of used medical or research equipment has always presented certain problems. These items may include contaminated syringes and needles, scalpels, blades, glass medication or drug dispensing ampules, intravenous sets, blood specimen containers, bandages and pads, surgical gloves, and many hundreds of other assorted instruments and supplies. Those items having pointed ends, such as syringes or needles, scalpels, blades, and other supplies capable of accidentally puncturing the skin or protective garments, have become known as "sharps."
The variety of such items has been steadily increasing over recent years and because disposability is a primary requirement for almost all medical supplies, the sheer number of such items being disposed of has also increased. These items are often contaminated--or must be treated as if contaminated--by an unknown variety of infectious or hazardous agents.
While it is accepted practice to separate radioactively contaminated waste from infectious or other hazardous wastes, it is often the case that radioactive wastes, infectious substances, viral or other biological contaminants, blood or tissue samples, unused medications, mutagenic compounds, and a host of other potential health hazards are disposed of together in common receptacles. The combining of such wastes creates additional problems, since any one may be more dangerous when in combination with another, and because it eliminates any chance for personnel to later identify what hazardous items may be in each receptacle.
Because many of these items are being used in medical facilities and research laboratories under conditions where the personnel must concentrate on a particular emergency at hand, where their activities are hampered by working in a sterile negative-pressure hood or other protective equipment, or must concentrate on performing many repetitive activities within a given time period, the disposal devices for such items must be made as safe, easy to use, and as relatively trouble or error free as possible.
Members of the medical community working with patients or in research facilities where communicable diseases such as Hepatitis-B, Staphylococcus, and the like may be present have shown considerable concern over the possible transmission of those communicable diseases through the accidental exposure to contaminated supplies, particularly to sharps. This concern has grown considerably in recent years, not just among those who routinely work with communicable diseases, but throughout the medical and public service sectors, due predominantly to widespread recognition of the increase in acquired immune deficiency syndrome (AIDS) cases. While there is a great deal of controversy surrounding the possible methods and likelihood of transmission of the AIDS viruses, it is well accepted that accidental contact with contaminated sharps presents one of the most dangerous threats of unintentional exposure to the AIDS virus for medical personnel.
It is important that the various types of wastes be disposed of appropriately. Some waste must be burned, while it is particularly dangerous to burn others. Some waste must first be sterilized, while others must be biologically or chemically neutralized. Others must be disposed of in a manner which will prevent any exposure to the environment. An additional consideration for disposing of particular sharps, specifically syringes and needles which are not burned, is the ongoing problem of preventing those needles from falling into the hands of intravenous (IV) drug users once they have been disposed of, since such needles are particularly valuable and many persons resort to combing through trash bins at hospitals or medical facilities in search of such items.
The governmental and institutionally self-imposed regulations for dealing with contaminated waste materials have become quiet expansive and confusing. It is therefore more efficient and practical for medical facilities of all sizes to place the responsibility for collecting, transporting, and disposing of infectious or other hazardous wastes in the hands of qualified professionals who perform this service. Consequently, the nature of the activities performed by these services gives rise to peculiar needs and considerations for the design of their disposal containers.
In the past, a variety of receptacles and disposal containers have been designed and used for the containment and disposal of infectious or hazardous wastes.
One feature which has been incorporated into a variety of different disposal containers is the "one way" closure. The one way closure is intended to seal the otherwise open neck of a disposal container, to prevent contaminants from becoming airborne, and to prevent sharps or other waste from falling or protruding out of the disposal container. Representative examples of such one way closures on disposal containers are shown in the U.S. Pat. Nos. 4,351,434; 4,454,944; and 3,381,814. The concept of a one way closure has also been utilized in other types of waste receptacles, such as that shown in U.S. Pat. No. 3,089,633 disclosing a trash container for use in automobiles, and in other types of products such as the dispensing carton disclosed in U. S. Pat. No. 3,556,293. The closure may range anywhere from a simple slit configuration as shown in U.S. Pat. No. 4,121,755, to shapes designed specifically for the disposal of particular items such as the system shown in the U.S. Pat. No. 4,625,877 for dispensing of syringe needles, and the star-like closure configurations of the patents mentioned above. While the closure is generally positioned on the top of the disposal container, it may in some instances be positioned on the side of the container, as shown in U.S. Pat. No. 3,494,536.
While being suitable for some applications, these disposal containers present several common deficiencies.
Medical personnel often injure themselves attempting to press sharps through the one way type closure. Since the person cannot see inside the container to determine if it is full, and the closure itself restricts the size and shape of certain articles which may pass through, persons may injure themselves attempting to force an item through the closure into a full container, or one which is not designed to accommodate the particular item. If an item becomes jammed in the closure, the person must use his finger to force the item into the container, which can result in piercing that finger with contaminated sharps or other objects which are pointed upwardly in the container.
The seal provided by such one way closures is generally not air tight, and therefore not suitable for use in the sterile environment required in many research facilities. Such closures are also subject to being deformed after continued use.
Many of the containers themselves are made from lightweight and non-durable materials so they can be disposed of, but consequently do not provide a complete seal around the periphery of the container or at its folds, and will permit liquid contaminants to leak out. More durable containers designed for repeated use, such as that shown in U.S. Pat. No. 4,454,944, may be constructed such that they can be autoclaved for sterilization, but are impractical to clean or empty.
One improvement has been the inclusion of a thin plastic liner, such as shown in U.S. Pat. Nos. 4,534,489 and 3,756,574. Such a liner is not practical in a container which is deformable or foldable, however, since items shifting within the flexible walls of the container will puncture the liner, or will protrude through folds and seams. Moreover, such a liner may restrict certain items from being placed within the container unless it is held open by the container rim, which then presents problems in maintaining the liner in an upright position around that rim when filled with any weight of saturated materials, liquids, or glassware.